I've always liked Britney as a performer and I was looking forward to seeing this documentary in the hope that she would reveal that she's gotten some insight into her life. If she has, it was displayed in the film at a sadly superficial level. She states she's had to "grow up" and she's "learned a lot" these past few difficult years, but from what is shown, I didn't actually see any profound evidence of it.
I was also hoping she would shed some light on her bizarre behavior regarding the court custody hearings, how she kept showing up late or not at all (yet in the course of the film she mentions more than once how dearly she loves her kids). And she never talks about the hospital incident either. All her statements seem to be planned out to reveal the least possible about herself; it's more like she was using the documentary for publicity.
Ironically, the only person who speaks from any genuine wisdom in the course of the film is Madonna, who talks about how a person creates his or her own reality and how Britney has at least begun the self-examination process by asking "What was I thinking" regarding this year's events.
At the end, she is asked how she will change her life to reflect her new so-called insights, and she responds by saying she will go through her life like "a karate kid." She then grins a self-satisfied grin, as if she's uttered something profound. She hasn't.